Maxwell's Equations in Vacuum

Q. The amplitude of the magnetic field part of a harmonic electromagnetic wave in vacuum is B0 = 510 nT. What is theamplitude of the electric field part of the wave?

Q.

The amplitude of the magnetic field part of a harmonic electromagnetic wave in a vacuum is $B_{\circ }=510nT$. What is the amplitude of the electric field part of the wave?

1. $140N{C}^{-1}$

2. $153N{C}^{-1}$

3. $163N{C}^{-1}$

4. $133N{C}^{-1}$

Q. In an experiment of photoelectric effect, the slope of the cut-off voltage versus frequency of incident light is found to be $4.2\times {10}^{-15}Vs$. Calculate the value of Plank's constant.

Q. Find the frequency of revolution of an electron with an energy of $100eV$ in a uniform magnetic field of magnitude $35.0\mu T$.

Q. An electric field of intensity $6\times {10}^{4}volts/m$ is applied perpendicular to the direction of motion of the electron. A magnetic field of intensity $8\times {10}^{-2}wb/m^2$ is applied perpendicular to both the electric field and direction of motion of the electron. What is the velocity of the electron if it passes undeflected?

1. $7.5\times {10}^{5}m/s$
2. $7.5\times {10}^{-5}m/s$
3. $6\times {10}^4\times 8\times {10}^{-2}m/s$
4. It is never possible

Q. Find the maximum $KE$ of photoelectrons emitted from the surface of lithium$(\varphi =2.39eV)$ when exposed with $E=E_0(1+\cos 6\times {10}^{14}t)\cos 3.6\times {10}^{15}t$

1. 0.1 $eV$
2. 0.06 $eV$
3. 0.37 $eV$
4. 0.02 $eV$